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Motor cortex (M1) has been thought to form a continuous somatotopic homunculus extending down the precentral gyrus from foot to face representations1,2, despite evidence for concentric functional zones3 and maps of complex actions4. Here, using precision functional magnetic resonance imaging (fMRI) methods, we find that the classic homunculus is interrupted by regions with distinct connectivity, structure and function, alternating with effector-specific (foot, hand and mouth) areas. These inter-effector regions exhibit decreased cortical thickness and strong functional connectivity to each other, as well as to the cingulo-opercular network (CON), critical for action5 and physiological control6, arousal7, errors8 and pain9. This interdigitation of action control-linked and motor effector regions was verified in the three largest fMRI datasets. Macaque and pediatric (newborn, infant and child) precision fMRI suggested cross-species homologues and developmental precursors of the inter-effector system. A battery of motor and action fMRI tasks documented concentric effector somatotopies, separated by the CON-linked inter-effector regions. The inter-effectors lacked movement specificity and co-activated during action planning (coordination of hands and feet) and axial body movement (such as of the abdomen or eyebrows). These results, together with previous studies demonstrating stimulation-evoked complex actions4 and connectivity to internal organs10 such as the adrenal medulla, suggest that M1 is punctuated by a system for whole-body action planning, the somato-cognitive action network (SCAN). In M1, two parallel systems intertwine, forming an integrate-isolate pattern: effector-specific regions (foot, hand and mouth) for isolating fine motor control and the SCAN for integrating goals, physiology and body movement.
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Mapeamento Encefálico , Cognição , Córtex Motor , Mapeamento Encefálico/métodos , Mãos/fisiologia , Imageamento por Ressonância Magnética , Córtex Motor/anatomia & histologia , Córtex Motor/fisiologia , Humanos , Recém-Nascido , Lactente , Criança , Animais , Macaca/anatomia & histologia , Macaca/fisiologia , Pé/fisiologia , Boca/fisiologia , Conjuntos de Dados como AssuntoRESUMO
The cerebral cortex is organized into distinct but interconnected cortical areas, which can be defined by abrupt differences in patterns of resting state functional connectivity (FC) across the cortical surface. Such parcellations of the cortex have been derived in adults and older infants, but there is no widely used surface parcellation available for the neonatal brain. Here, we first demonstrate that existing parcellations, including surface-based parcels derived from older samples as well as volume-based neonatal parcels, are a poor fit for neonatal surface data. We next derive a set of 283 cortical surface parcels from a sample of n = 261 neonates. These parcels have highly homogenous FC patterns and are validated using three external neonatal datasets. The Infomap algorithm is used to assign functional network identities to each parcel, and derived networks are consistent with prior work in neonates. The proposed parcellation may represent neonatal cortical areas and provides a powerful tool for neonatal neuroimaging studies.
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Encéfalo , Imageamento por Ressonância Magnética , Adulto , Recém-Nascido , Humanos , Imageamento por Ressonância Magnética/métodos , Neuroimagem , Córtex Cerebral/diagnóstico por imagem , Algoritmos , Processamento de Imagem Assistida por Computador/métodosRESUMO
PURPOSE/BACKGROUND: Brexanolone is approved for postpartum depression (PPD) by the United States Food and Drug Administration. Brexanolone has outperformed placebo in clinical trials, but less is known about the efficacy in real-world patients with complex social and medical histories. Furthermore, the impact of brexanolone on large-scale brain systems such as changes in functional connectivity (FC) is unknown. METHODS/PROCEDURES: We tracked changes in depressive symptoms across a diverse group of patients who received brexanolone at a large medical center. Edinburgh Postnatal Depression Scale (EPDS) scores were collected through chart review for 17 patients immediately prior to infusion through approximately 1 year postinfusion. In 2 participants, we performed precision functional neuroimaging (pfMRI), including before and after treatment in 1 patient. pfMRI collects many hours of data in individuals for precision medicine applications and was performed to assess the feasibility of investigating changes in FC with brexanolone. FINDINGS/RESULTS: The mean EPDS score immediately postinfusion was significantly lower than the mean preinfusion score (mean change [95% CI]: 10.76 [7.11-14.40], t (15) = 6.29, P < 0.0001). The mean EPDS score stayed significantly lower at 1 week (mean difference [95% CI]: 9.50 [5.23-13.76], t (11) = 4.90, P = 0.0005) and 3 months (mean difference [95% CI]: 9.99 [4.71-15.27], t (6) = 4.63, P = 0.0036) postinfusion. Widespread changes in FC followed infusion, which correlated with EPDS scores. IMPLICATIONS/CONCLUSIONS: Brexanolone is a successful treatment for PPD in the clinical setting. In conjunction with routine clinical care, brexanolone was linked to a reduction in symptoms lasting at least 3 months. pfMRI is feasible in postpartum patients receiving brexanolone and has the potential to elucidate individual-specific mechanisms of action.
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Depressão Pós-Parto , Estudos de Viabilidade , Pregnanolona , beta-Ciclodextrinas , Humanos , Feminino , Adulto , Pregnanolona/administração & dosagem , Pregnanolona/farmacologia , Projetos Piloto , Depressão Pós-Parto/tratamento farmacológico , beta-Ciclodextrinas/administração & dosagem , beta-Ciclodextrinas/farmacologia , Neuroimagem Funcional , Combinação de Medicamentos , Adulto Jovem , Resultado do Tratamento , Encéfalo/efeitos dos fármacos , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância MagnéticaRESUMO
The adult human brain is organized into functional brain networks, groups of functionally connected segregated brain regions. A key feature of adult functional networks is long-range selectivity, the property that spatially distant regions from the same network have higher functional connectivity than spatially distant regions from different networks. Although it is critical to establish the status of functional networks and long-range selectivity during the neonatal period as a foundation for typical and atypical brain development, prior work in this area has been mixed. Although some studies report distributed adult-like networks, other studies suggest that neonatal networks are immature and consist primarily of spatially isolated regions. Using a large sample of neonates (n = 262), we demonstrate that neonates have long-range selective functional connections for the default mode, fronto-parietal, and dorsal attention networks. An adult-like pattern of functional brain networks is evident in neonates when network-detection algorithms are tuned to these long-range connections, when using surface-based registration (versus volume-based registration), and as per-subject data quantity increases. These results help clarify factors that have led to prior mixed results, establish that key adult-like functional network features are evident in neonates, and provide a foundation for studies of typical and atypical brain development.
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Mapeamento Encefálico , Imageamento por Ressonância Magnética , Adulto , Recém-Nascido , Humanos , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , Vias Neurais , Encéfalo , Processamento de Imagem Assistida por Computador , Rede NervosaRESUMO
The period immediately after birth is a critical developmental window, capturing rapid maturation of brain structure and a child's earliest experiences. Large-scale brain systems are present at delivery, but how these brain systems mature during this narrow window (i.e. first weeks of life) marked by heightened neuroplasticity remains uncharted. Using multivariate pattern classification techniques and functional connectivity magnetic resonance imaging, we detected robust differences in brain systems related to age in newborns (n = 262; R2 = 0.51). Development over the first month of life occurred brain-wide, but differed and was more pronounced in brain systems previously characterized as developing early (i.e. sensorimotor networks) than in those characterized as developing late (i.e. association networks). The cingulo-opercular network was the only exception to this organizing principle, illuminating its early role in brain development. This study represents a step towards a normative brain "growth curve" that could be used to identify atypical brain maturation in infancy.
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Mapeamento Encefálico , Encéfalo , Criança , Humanos , Recém-Nascido , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , Córtex Insular , Vias Neurais/diagnóstico por imagemRESUMO
BACKGROUND: Preliminary work suggests anxiety moderates the relationship between irritability and bullying. As anxiety increases, the link between irritability and perpetration decreases. We hypothesize that any moderation effect of anxiety is driven by social anxiety symptoms. We sought to explicate the moderating effect of anxiety, while clarifying relations to other aggressive behaviors. METHODS: A sample of adolescents (n = 169, mean = 12.42 years of age) were assessed using clinician rated assessments of anxiety, parent reports of irritability and bullying behaviors (perpetration, generalized aggression, and victimization). Correlations assessed zero-order relations between variables, and regression-based moderation analyses were used to test interactions. Johnson-Neyman methods were used to represent significant interactions. RESULTS: Irritability was significantly related to bullying (r = .403, p < .001). Social, but not generalized, anxiety symptoms significantly moderated the effect of irritability on bully perpetration (t(160) = -2.94, b = -.01, p = .0038, ΔR2 = .0229, F(1, 160) = 8.635). As social anxiety symptoms increase, the link between irritability and perpetration decreases. CONCLUSIONS: Understanding how psychopathology interacts with social behaviors is of great importance. Higher social anxiety is linked to reduced relations between irritability and bullying; however, the link between irritability and other aggression remains positive. Comprehensively assessing how treatment of psychopathology impacts social behaviors may improve future intervention.
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The hippocampus is critically important for a diverse range of cognitive processes, such as episodic memory, prospective memory, affective processing, and spatial navigation. Using individual-specific precision functional mapping of resting-state functional MRI data, we found the anterior hippocampus (head and body) to be preferentially functionally connected to the default mode network (DMN), as expected. The hippocampal tail, however, was strongly preferentially functionally connected to the parietal memory network (PMN), which supports goal-oriented cognition and stimulus recognition. This anterior-posterior dichotomy of resting-state functional connectivity was well-matched by differences in task deactivations and anatomical segmentations of the hippocampus. Task deactivations were localized to the hippocampal head and body (DMN), relatively sparing the tail (PMN). The functional dichotomization of the hippocampus into anterior DMN-connected and posterior PMN-connected parcels suggests parallel but distinct circuits between the hippocampus and medial parietal cortex for self- versus goal-oriented processing.
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Mapeamento Encefálico , Hipocampo/fisiologia , Rede Nervosa/fisiologia , Lobo Parietal/fisiologia , Adulto , Bases de Dados Factuais , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Memória Episódica , Vias Neurais , Análise e Desempenho de Tarefas , Adulto JovemRESUMO
The amygdala is central to the pathophysiology of many psychiatric illnesses. An imprecise understanding of how the amygdala fits into the larger network organization of the human brain, however, limits our ability to create models of dysfunction in individual patients to guide personalized treatment. Therefore, we investigated the position of the amygdala and its functional subdivisions within the network organization of the brain in 10 highly sampled individuals (5 h of fMRI data per person). We characterized three functional subdivisions within the amygdala of each individual. We discovered that one subdivision is preferentially correlated with the default mode network; a second is preferentially correlated with the dorsal attention and fronto-parietal networks; and third subdivision does not have any networks to which it is preferentially correlated relative to the other two subdivisions. All three subdivisions are positively correlated with ventral attention and somatomotor networks and negatively correlated with salience and cingulo-opercular networks. These observations were replicated in an independent group dataset of 120 individuals. We also found substantial across-subject variation in the distribution and magnitude of amygdala functional connectivity with the cerebral cortex that related to individual differences in the stereotactic locations both of amygdala subdivisions and of cortical functional brain networks. Finally, using lag analyses, we found consistent temporal ordering of fMRI signals in the cortex relative to amygdala subdivisions. Altogether, this work provides a detailed framework of amygdala-cortical interactions that can be used as a foundation for models relating aberrations in amygdala connectivity to psychiatric symptoms in individual patients.
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Tonsila do Cerebelo/fisiologia , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Atenção , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Mapeamento Encefálico , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiologia , Feminino , Humanos , Individualidade , Imageamento por Ressonância Magnética , Masculino , Psiquiatria , Adulto JovemRESUMO
The goal of precision medicine (individually tailored treatments) is not being achieved for neurobehavioural conditions such as psychiatric disorders. Traditional randomized clinical trial methods are insufficient for advancing precision medicine because of the dynamic complexity of these conditions. We present a pragmatic solution: the precision clinical trial framework, encompassing methods for individually tailored treatments. This framework includes the following: (1) treatment-targeted enrichment, which involves measuring patients' response after a brief bout of an intervention, and then randomizing patients to a full course of treatment, using the acute response to predict long-term outcomes; (2) adaptive treatments, which involve adjusting treatment parameters during the trial to individually optimize the treatment; and (3) precise measurement, which involves measuring predictor and outcome variables with high accuracy and reliability using techniques such as ecological momentary assessment. This review summarizes precision clinical trials and provides a research agenda, including new biomarkers such as precision neuroimaging, transcranial magnetic stimulation-electroencephalogram digital phenotyping and advances in statistical and machine-learning models. Validation of these approaches - and then widespread incorporation of the precision clinical trial framework - could help achieve the vision of precision medicine for neurobehavioural conditions.
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Ensaios Clínicos como Assunto , Transtornos Mentais/diagnóstico , Transtornos Mentais/terapia , Doenças do Sistema Nervoso/diagnóstico , Doenças do Sistema Nervoso/terapia , Avaliação de Resultados em Cuidados de Saúde , Medicina de Precisão , Projetos de Pesquisa , Ensaios Clínicos como Assunto/métodos , Ensaios Clínicos como Assunto/normas , Humanos , Avaliação de Resultados em Cuidados de Saúde/métodos , Avaliação de Resultados em Cuidados de Saúde/normas , Medicina de Precisão/métodos , Medicina de Precisão/normas , Projetos de Pesquisa/normasRESUMO
The characterizing features of autism spectrum disorder (ASD) are continuously distributed in nature; however, prior twin studies have not systematically incorporated this knowledge into estimations of concordance and discordance. We conducted a quantitative analysis of twin-twin similarity for autistic trait severity in three existing data sets involving 366 pairs of uniformly-phenotyped monozygotic (MZ) twins with and without ASD. Probandwise concordance for ASD was 96%; however, MZ trait correlations differed markedly for pairs with ASD trait burden below versus above the threshold for clinical diagnosis, with R2s on the order of 0.6 versus 0.1, respectively. Categorical MZ twin discordance for ASD diagnosis is rare and more appropriately operationalized by standardized quantification of twin-twin differences. Here we provide new evidence that although ASD itself is highly heritable, variation-in-severity of symptomatology above the diagnostic threshold is substantially influenced, in contrast, by non-shared environmental factors which may identify novel targets of early ASD amelioration.
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Transtorno do Espectro Autista/genética , Doenças em Gêmeos/genética , Adolescente , Transtorno Autístico/genética , Criança , Pré-Escolar , Bases de Dados Factuais , Bases de Dados Genéticas , Feminino , Interação Gene-Ambiente , Estudos de Associação Genética , Predisposição Genética para Doença/genética , Genótipo , Humanos , Masculino , Fenótipo , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genéticaRESUMO
High shyness during early adolescence is associated with impaired peer relationships and risk for psychiatric disorders. Little is known, however, about the relation between shyness and trajectories of brain development over early adolescence. The current study longitudinally examined trajectories of resting-state functional connectivity (rs-fc) within four brain networks in 147 adolescents. Subjects underwent functional magnetic resonance imaging at three different time points, at average ages 10.5 (range = 7.8-13.0), 11.7 (range = 9.3-14.1), and 12.9 years (range = 10.1-15.2). Multilevel linear modeling indicated that high shyness was associated with a less steep negative slope of default mode network (DMN) rs-fc over early adolescence relative to low shyness. Less steep decreases in DMN rs-fc may relate to increased self-focus in adolescents with high shyness.
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Comportamento do Adolescente/fisiologia , Encéfalo/fisiologia , Comportamento Infantil/fisiologia , Conectoma/métodos , Rede Nervosa/fisiologia , Timidez , Adolescente , Encéfalo/diagnóstico por imagem , Encéfalo/crescimento & desenvolvimento , Criança , Feminino , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/crescimento & desenvolvimentoRESUMO
OBJECTIVES: To determine if late preterm (LP) children differ from full term (FT) children in volumes of the cortex, hippocampus, corpus callosum, or amygdala and whether these differences are associated with anxiety symptoms at school-age. STUDY DESIGN: LP children born between 34 and 36 weeks gestation and FT children born between 39 and 41 weeks gestation from a larger longitudinal cohort had magnetic resonance imaging scans at school-age. Brain volumes, cortical surface area, and thickness measures were obtained. Anxiety symptoms were assessed using a structured diagnostic interview annually beginning at preschool-age and following the magnetic resonance imaging. RESULTS: LP children (n = 21) had a smaller percentage of total, right parietal, and right temporal lobe gray matter volume than FT children (n = 87). There were no differences in hippocampal, callosal, or amygdala volumes or cortical thickness. LP children also had a relative decrease in right parietal lobe cortical surface area. LP children had greater anxiety symptoms over all assessments. The relationship between late prematurity and school-age anxiety symptoms was mediated by the relative decrease in right temporal lobe volume. CONCLUSIONS: LP children, comprising 70% of preterm children, are also at increased risk for altered brain development particularly in the right temporal and parietal cortices. Alterations in the right temporal lobe cortical volume may underlie the increased rate of anxiety symptoms among these LP children. These findings suggest that LP delivery may disrupt temporal and parietal cortical development that persists until school-age with the right temporal lobe conferring risk for elevated anxiety symptoms.
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Transtornos de Ansiedade/etiologia , Substância Cinzenta/patologia , Recém-Nascido Prematuro , Nascimento Prematuro , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Imageamento por Ressonância Magnética , MasculinoRESUMO
Pediatric anxiety and depressive disorders are common, can be highly impairing, and can persist despite the best available treatments. Here, we review research into novel treatments for childhood anxiety and depressive disorders designed to target underlying cognitive, emotional, and neural circuit mechanisms. We highlight three novel treatments lying along a continuum relating to clinical impact of the disorder and the intensity of clinical management required. We review cognitive training, which involves the lowest risk and may be applicable for problems with mild to moderate impact; psychotherapy, which includes a higher level of clinical involvement and may be sufficient for problems with moderate impact; and brain stimulation, which has the highest potential risks and is therefore most appropriate for problems with high impact. For each treatment, we review the specific underlying cognitive, emotional, and brain circuit mechanisms that are being targeted, whether treatments modify those underlying mechanisms, and efficacy in reducing symptoms. We conclude by highlighting future directions, including the importance of work that leverages developmental windows of high brain plasticity to time interventions to the specific epochs in childhood that have the largest and most enduring life-long impact.
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Transtornos de Ansiedade , Transtorno Depressivo , Humanos , Criança , Transtornos de Ansiedade/terapia , Ansiedade , Psicoterapia , Emoções , Transtorno Depressivo/terapiaRESUMO
Neuroplasticity during sensitive periods, the molecular and cellular process of enduring neural change in response to external stimuli during windows of high environmental sensitivity, is crucial for adaptation to expected environments and has implications for psychiatry. Animal research has characterized the developmental sequence and neurobiological mechanisms that govern neuroplasticity, yet gaps in our ability to measure neuroplasticity in humans limit the clinical translation of these principles. Here, we present a roadmap for the development and validation of neuroimaging and electrophysiology measures that index neuroplasticity to begin to address these gaps. We argue that validation of measures to track neuroplasticity in humans will elucidate the etiology of mental illness and inform the type and timing of mental health interventions to optimize effectiveness. We outline criteria for evaluating putative neuroimaging measures of plasticity in humans including links to neurobiological mechanisms shown to govern plasticity in animal models, developmental change that reflects heightened early life plasticity, and prediction of neural and/or behavior change. These criteria are applied to three putative measures of neuroplasticity using electroencephalography (gamma oscillations, aperiodic exponent of power/frequency) or functional magnetic resonance imaging (amplitude of low frequency fluctuations). We discuss the use of these markers in psychiatry, envision future uses for clinical and developmental translation, and suggest steps to address the limitations of the current putative neuroimaging measures of plasticity. With additional work, we expect these markers will significantly impact mental health and be used to characterize mechanisms, devise new interventions, and optimize developmental trajectories to reduce psychopathology risk.
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OBJECTIVE: Resource deprivation is linked to systemic factors that disproportionately impact historically marginalized communities, and theoretical work suggests that resource deprivation may increase risk for bullying behaviors. Bullying perpetration is an intransigent social problem and an early risk factor that perpetuates the school-to-prison pipeline. This study explored how resource deprivation (family- and neighborhood-level metrics) was associated with early childhood bullying behaviors and clinician-rated symptoms of psychopathology, while accounting for other known risk factors (early life stressors, traumatic events, parental arrest, domestic violence). METHOD: Participants (306 children, mean age = 4.45 years) were enrolled in a longitudinal study (Preschool Depression Study) where demographics, clinician-rated assessments of psychopathology, and parent reports of social functioning were collected. Measures of bullying behaviors (bullying perpetration, generalized aggression, and victimization) were constructed. A cross-sectional approach was employed, and analyses examined the interrelations between race, bullying-related behaviors, resource deprivation, and psychopathology, while accounting for confounding variables, at the baseline assessment time point. RESULTS: The bullying measure showed acceptable model fit (comparative fit index = 0.956, Tucker-Lewis index = 0.945, root mean square error of approximation = 0.061, standardized root mean residual = 0.052, normed χ2 ratio = 2). Neighborhood resource deprivation was more strongly associated with bullying perpetration (r = 0.324, p < .001) than generalized aggression (r = 0.236, Williams t303 = 2.11, p = .036) and remained significant when controlling for other known risk factors (parental arrests, domestic violence, stressors, traumas) and demographic factors. Bullying perpetration was linked with racial category, but the relation was fully mediated by neighborhood resource deprivation. Linear regression including bullying behaviors and symptoms of clinical psychopathology suggested that resource deprivation specifically led to increases in bullying perpetration (t = 2.831, p = .005) and clinician-rated symptoms of conduct disorder (t = 2.827, p = .005), which were attributable to increased rates of resource-driven conduct symptoms (bullies, lies to obtain goods, stolen without confrontation). CONCLUSION: Resource deprivation is strongly and specifically associated with increases in bullying perpetration. Children growing up in impoverished neighborhoods show significant increases in resource-driven conduct behaviors, yet interventions often target individual-level factors. These results highlight the need to target social inequity to reduce bullying perpetration and suggest that interventions targeting neighborhoods should be tested to reduce bullying in early childhood. DIVERSITY & INCLUSION STATEMENT: We worked to ensure sex and gender balance in the recruitment of human participants. We worked to ensure race, ethnic, and/or other types of diversity in the recruitment of human participants. We worked to ensure that the study questionnaires were prepared in an inclusive way. One or more of the authors of this paper self-identifies as a member of one or more historically underrepresented racial and/or ethnic groups in science. While citing references scientifically relevant for this work, we also actively worked to promote sex and gender balance in our reference list. We actively worked to promote inclusion of historically underrepresented racial and/or ethnic groups in science in our author group. One or more of the authors of this paper received support from a program designed to increase minority representation in science. One or more of the authors of this paper self-identifies as a member of one or more historically underrepresented sexual and/or gender groups in science. One or more of the authors of this paper self-identifies as living with a disability. We actively worked to promote sex and gender balance in our author group. While citing references scientifically relevant for this work, we also actively worked to promote inclusion of historically underrepresented racial and/or ethnic groups in science in our reference list.
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Functional brain network studies using the Blood Oxygen-Level Dependent (BOLD) signal from functional Magnetic Resonance Imaging (fMRI) are becoming increasingly prevalent in research on the neural basis of human cognition. An important problem in functional brain network analysis is to understand directed functional interactions between brain regions during cognitive performance. This problem has important implications for understanding top-down influences from frontal and parietal control regions to visual occipital cortex in visuospatial attention, the goal motivating the present study. A common approach to measuring directed functional interactions between two brain regions is to first create nodal signals by averaging the BOLD signals of all the voxels in each region, and to then measure directed functional interactions between the nodal signals. Another approach, that avoids averaging, is to measure directed functional interactions between all pairwise combinations of voxels in the two regions. Here we employ an alternative approach that avoids the drawbacks of both averaging and pairwise voxel measures. In this approach, we first use the Least Absolute Shrinkage Selection Operator (LASSO) to pre-select voxels for analysis, then compute a Multivariate Vector AutoRegressive (MVAR) model from the time series of the selected voxels, and finally compute summary Granger Causality (GC) statistics from the model to represent directed interregional interactions. We demonstrate the effectiveness of this approach on both simulated and empirical fMRI data. We also show that averaging regional BOLD activity to create a nodal signal may lead to biased GC estimation of directed interregional interactions. The approach presented here makes it feasible to compute GC between brain regions without the need for averaging. Our results suggest that in the analysis of functional brain networks, careful consideration must be given to the way that network nodes and edges are defined because those definitions may have important implications for the validity of the analysis.
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Algoritmos , Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Imageamento por Ressonância Magnética/métodos , Modelos Neurológicos , Rede Nervosa/fisiologia , Transmissão Sináptica/fisiologia , Animais , Simulação por Computador , Humanos , Modelos EstatísticosRESUMO
Psychiatric disorders are complex, often emerging from multiple atypical processes within specified domains over the course of development. Characterizing the development of the neural circuits supporting these domains may help break down the components of complex disorders and reveal variations in functioning associated with psychiatric risk. This review highlights the current and potential role of infant task-based functional magnetic resonance imaging (fMRI) in elucidating the developmental neurobiology of psychiatric disorders. Task-fMRI measures evoked brain activity in response to specific stimuli through changes in the blood oxygen level-dependent signal. First, we review extant studies using task fMRI from birth through the first few years of life and synthesize current evidence for when, where, and how different neural computations are performed across the infant brain. Neural circuits for sensory perception, the perception of abstract categories, and the detection of statistical regularities have been characterized with task fMRI in infants, providing developmental context for identifying and interpreting variation in the functioning of neural circuits related to psychiatric risk. Next, we discuss studies that specifically examine variation in the functioning of these neural circuits during infancy in relation to risk for psychiatric disorders. These studies reveal when maturation of specific neural circuits diverges, the influence of environmental risk factors, and the potential utility for task fMRI to facilitate early treatment or prevention of later psychiatric problems. Finally, we provide considerations for future infant task-fMRI studies with the potential to advance understanding of both functioning of neural circuits during infancy and subsequent risk for psychiatric disorders.
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Encéfalo , Transtornos Mentais , Lactente , Humanos , Encéfalo/diagnóstico por imagem , Transtornos Mentais/diagnóstico por imagem , Imageamento por Ressonância MagnéticaRESUMO
Humans require a shared conceptualization of others' emotions for adaptive social functioning. A concept is a mental blueprint that gives our brains parameters for predicting what will happen next. Emotion concepts undergo refinement with development, but it is not known whether their neural representations change in parallel. Here, in a sample of 5-15-year-old children (n = 823), we show that the brain represents different emotion concepts distinctly throughout the cortex, cerebellum and caudate. Patterns of activation to each emotion changed little across development. Using a model-free approach, we show that activation patterns were more similar between older children than between younger children. Moreover, scenes that required inferring negative emotional states elicited higher default mode network activation similarity in older children than younger children. These results suggest that representations of emotion concepts are relatively stable by mid to late childhood and synchronize between individuals during adolescence.
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Encéfalo , Emoções , Humanos , Criança , Adolescente , Pré-Escolar , Emoções/fisiologia , Encéfalo/fisiologia , Córtex Cerebral/fisiologia , Imageamento por Ressonância MagnéticaRESUMO
OBJECTIVE: Social anxiety is associated with alterations in socioemotional processing, but the pathophysiology remains poorly understood. Movies present an opportunity to examine more naturalistic socioemotional processing by providing narrative and sensory context to emotion cues. This study aimed to characterize associations between neural response to contextualized social cues and social anxiety symptoms in children. METHOD: Data from the Healthy Brain Network (final N = 740; age range 5-15 years) were split into discovery and replication samples to maximize generalizability of findings. Associations of parent- and self-reported social anxiety (Screen for Child Anxiety-related Emotional Disorders) with mean differences and person-to-person variability in functional magnetic resonance imaging-measured activation to 2 emotionally dynamic movies were characterized. RESULTS: Though no evidence was found to indicate social anxiety symptoms were associated with mean differences in neural activity to emotional content (fit Spearman rs < 0.09), children with high social anxiety symptoms had higher intersubject activation variability in the posterior cingulate, supramarginal gyrus, and inferior frontal gyrus (Bonferroni familywise error-corrected ps < .05)-regions associated with attention, alertness, and emotion cue processing. Identified regions varied by age group and informant. Across ages, these effects were enhanced for scenes containing greater sensory intensity (brighter, louder, more motion, more vibrance). CONCLUSION: These results provide evidence that children with high social anxiety symptoms show high person-to-person variability in the neural processing of sensory aspects of emotional content. These data indicate that children with high social anxiety may require personalized interventions for sensory and emotional difficulties, as the underlying neurology differs from child to child. DIVERSITY & INCLUSION STATEMENT: One or more of the authors of this paper self-identifies as a member of one or more historically underrepresented racial and/or ethnic groups in science. One or more of the authors of this paper self-identifies as a member of one or more historically underrepresented sexual and/or gender groups in science. One or more of the authors of this paper received support from a program designed to increase minority representation in science. We actively worked to promote sex and gender balance in our author group. We actively worked to promote inclusion of historically underrepresented racial and/or ethnic groups in science in our author group. While citing references scientifically relevant for this work, we also actively worked to promote sex and gender balance in our reference list. While citing references scientifically relevant for this work, we also actively worked to promote inclusion of historically underrepresented racial and/or ethnic groups in science in our reference list.
RESUMO
Objective: Pediatric anxiety disorders are associated with increased stimulus-driven attention (SDA), the involuntary capture of attention by salient stimuli. Increased SDA is linked to increased activity in the right ventrolateral prefrontal cortex (rVLPFC), especially in the portion corresponding to the ventral attention network (VAN). In this study, we present a small clinical trial using a novel attention training program designed to treat pediatric anxiety by decreasing SDA and activity in the rVLPFC. Methods: Children ages 8-12 with anxiety disorders (n = 18) participated in eight sessions of attention training over a 4-week period. At baseline and after completing training, participants completed clinical anxiety measures and a battery of cognitive tasks designed to measure three different aspects of attention: SDA, goal-oriented attention, and threat bias. A subset of participants (n = 12) underwent baseline and post-training neuroimaging while engaged in an SDA task. Brain analyses focused on activity within the rVLPFC. Results: Parent (p < 0.001)-, child (p < 0.002)-, and clinician-rated (p < 0.02) anxiety improved significantly over the course of training. Training significantly altered SDA [F(1,92) = 8.88, corrected p-value (pcor) < 0.012, uncorrected p-value (puncor) < 0.004]. Anxiety improvement correlated with improvements in goal-directed attention [r(10) = 0.60, pcor < 0.12 puncor < 0.04]. Within an area of the rVLPFC corresponding to the cingulo-opercular network (CON), there was a main effect of training [F(1,20) = 6.75, pcor < 0.16, puncor < 0.02], with decreasing signal across training. There was a significant interaction between training and anxiety on this region's activity [F(1,20) = 9.48, pcor < 0.048, puncor < 0.006]. Post hoc testing revealed that post-training activity within this CON area correlated with residual anxiety [r(10) = 0.68, p < 0.02]. Conclusions: SDA and rVLPFC neural activity may be novel therapeutic targets in pediatric anxiety. After undergoing a training paradigm aimed at modifying this aspect of attention and its underlying neural circuitry, patients showed lower anxiety, changes in SDA and goal-oriented attention, and decreased activity in the CON portion of the rVLPFC.